SUPERCONDUCTIVITY WITH S AND P SYMMETRIES IN AN EXTENDED HUBBARD-MODEL WITH CORRELATED HOPPING

We consider a generalized Hubbard model with on-site and nearest-neigh bour repulsions U and V respectively, and nearest-neighbour hopping fa r spin up (down) which depends on the total occupation n(b) of spin do wn (up) electrons on both sites involved. The hopping parameters are t (AA), t(AB) and t(BB) for n(b) = 0, 1, 2 respectively. We briefly summ arize results which support that the model exhibits s-wave superconduc tivity for certain parameters and extend them by studying the Berry ph ases. Using a generalized Hartree-Fock(HF) BCS decoupling of the two a nd three-body terms, we obtain that at half filling, for t(AB) < t(AA) = t(BB) and sufficiently small U and V the model leads to triplet p-w ave superconductivity for a simple cubic lattice in any dimension. In one dimension, the resulting phase diagram is compared with that obtai ned numerically using two quantized Berry phases (topological numbers) as order parameters. While this novel method supports the previous re sults, there are quantitative differences.